A robber stole cash and cigarettes from a Lincoln shop after he threatened a staff member with a knife.
The incident took place on Friday, January 27, at Keddington Stores in Keddington Avenue, at around 4.55pm.
The offender is described as white, between 6ft and 6ft 2in tall, wearing a green coat and dark blue jeans. He was also wearing a high-vis tabard.
Police are appealing for any witnesses, or anyone with any information to get in touch with them as soon as possible.
You can call DC Nick Hakes via the non-emergency 101 number, or call independent charity Crimestoppers anonymously on 0800 555 111.